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    <title>nehari</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>nehari</b> -  Nehari approximant</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>[x]=nehari(R [,tol])  </tt>
      </dd>
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    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>R</b>
        </tt>: linear system (<tt>
          <b>syslin</b>
        </tt> list)</li>
      <li>
        <tt>
          <b>x</b>
        </tt>: linear system (<tt>
          <b>syslin</b>
        </tt> list)</li>
      <li>
        <tt>
          <b>tol</b>
        </tt>: optional threshold</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>[x]=nehari(R [,tol])returns</b>
      </tt> the Nehari approximant of <tt>
        <b>R</b>
      </tt>.</p>
    <p>
      <tt>
        <b>R</b>
      </tt> = linear system in state-space representation (<tt>
        <b>syslin</b>
      </tt> list).</p>
    <p>
      <tt>
        <b>R</b>
      </tt> is strictly proper and <tt>
        <b>- R~</b>
      </tt> is stable 
    (i.e. <tt>
        <b>R</b>
      </tt> is anti stable).</p>
    <pre>

    || R - X ||oo = min || R - Y ||oo
                  Y in Hoo
   
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